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GeneralTo star or not to star...
29th Dec 2019 17:38 UTCMatt Courville
Hello, I had stumbled recently upon the 'Star of Adam' Blue Star Sapphire as posted and was thinking to myself as a field collector and lapidary enthusiast about the staring effect of corundum in general. Perhaps someone might be able to clarify some thoughts... Say one were to collected many dozen corundum crystals of any color and wished to know whether or not to trim, cut and polish these into what could be 'star-ing effects' what would determine choosing one over the other?
Should the rough corundum already have an effect present, or is it trial and error. When looking at the photo which I had posted I see a beautiful polished highly valuable piece that could have possibly looked like a non-transparent, non-translucent, blue-ish chunk of what could have been a poorly terminated crystal; and therefore seemingly a large shelf piece.
Any thoughts, as I would love to wrap my head around the decision making process of what is 'worthy' ;)
Matt
29th Dec 2019 17:54 UTCPeter Slootweg 🌟
29th Dec 2019 18:04 UTCcascaillou
Beware of fakes (asterism in corundum can be intensified or created from heat treatment or titanium-diffusion treatment, there is also asteriated synthetic corundum, you might also encounter cabbed doublet stones with asterism, etc...not to mention that a stone with a 100% natural star could still have been treated just to improve its color and/or clarity)
29th Dec 2019 18:09 UTCKevin Conroy Manager
29th Dec 2019 18:45 UTCMatt Courville
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Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 25, 2024 13:02:42